Direct cyanation, hydrocyanation, dicyanation and cyanofunctionalization of alkynes

RSC Advances, Journal Year: 2020, Volume and Issue: 10(17), P. 10232 - 10244

Published: Jan. 1, 2020

In this review, direct cyanation, hydrocyanation, dicyanation, cyanofunctionalization and other cyanation reactions of alkynes were highlighted. Firstly, the use nitriles development was simply introduced. After presenting natural properties alkynes, classified introduced in detail. Transition metal catalysed hydrocyanation gave alkynyl cyanides alkenyl good yields. Dicyanation produced 1,2-dicyano adducts. Cyanofunctionalization afforded functional cyanated compounds. Thiocyanation selenocyanation yielded expected vinylthiocyanates vinylselenocyanates. A plausible reaction mechanism is presented if available.

Language: Английский

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Air‐stable zirconium (IV)‐salophen perfluorooctanesulfonate as a highly efficient and reusable catalyst for the synthesis of 3,4‐dihydropyrimidin‐2‐(1H)‐ones/thiones under solvent‐free conditions

Applied Organometallic Chemistry, Journal Year: 2019, Volume and Issue: 34(3)

Published: Dec. 30, 2019

An air‐stable complex of zirconium (IV)‐salophen perfluorooctanesulfonate ( 1 ) was successfully synthesized by reacting Zr (salphen)Cl 2 and C 8 F 17 SO 3 Ag. Complex characterized studied different techniques (NMR, IR, HRMS, TG‐DSC, conductivity acidity measurements), found to be air‐stable, water tolerant, thermally stable strongly Lewis‐acidic. exhibited high catalytic efficiency for the synthesis 3,4‐dihydropyrimidin‐2‐(1H)‐ones/thiones via Biginelli reaction aldehydes, 1,3‐dicarbonyl compounds urea/thiourea under solvent‐free conditions. Furthermore, could reused 5 times with minimal changes in efficiency. Compared previously reported methods, important features this protocol are conditions, short times, wide substrate compatibility, good reusability.

Language: Английский

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Alkaline-Earth Metal Catalyzed Dehydrative Allylic Alkylation

Organic Letters, Journal Year: 2019, Volume and Issue: 22(1), P. 31 - 35

Published: Dec. 16, 2019

An alkaline-earth metal catalytic system for environmentally benign allylic alkylation was developed. Allylic alcohols can be utilized directly at room temperature in this transition-metal-free process, producing water as the only byproduct. A variety of compounds, including ones containing all-carbonyl quaternary centers, obtained with high yields.

Language: Английский

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Combined Use of Deep Eutectic Solvents, Macroporous Resins, and Preparative Liquid Chromatography for the Isolation and Purification of Flavonoids and 20-Hydroxyecdysone from Chenopodium quinoa Willd

Biomolecules, Journal Year: 2019, Volume and Issue: 9(12), P. 776 - 776

Published: Nov. 25, 2019

Deep eutectic solvents (DESs) were used in combination with macroporous resins to isolate and purify flavonoids 20-hydroxyecdysone from Chenopodium quinoa Willd by preparative high-performance liquid chromatography (HPLC). The extraction performances of six DESs the adsorption/desorption five (AB-8, D101, HPD 400, 600, NKA-9) investigated using total flavonoid yields as evaluation criteria, best-performing DES (choline chloride/urea, DES-6) resin (D101) further employed for phytochemical removal, respectively. purified extract was subjected HPLC, collected fractions a successive round HPLC three 20-hydroxyecdysone, which identified spectroscopic techniques. use this study significantly facilitated preparative-scale isolation purification polar phytochemicals complex plant systems.

Language: Английский

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Transition-metal-free sulfonylations of methylthiolated alkynones to synthesize 3-sulfonylated thioflavones

New Journal of Chemistry, Journal Year: 2020, Volume and Issue: 44(35), P. 14786 - 14790

Published: Jan. 1, 2020

A set of transition-metal-free NaI/TBHP-mediated sulfonylation cyclization reactions methylthiolated alkynones with sulfonyl hydrazides was developed, by which various 3-sulfonylated thioflavones were prepared under mild reaction conditions.

Language: Английский

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